The present invention relates to an oven for continuous curing of a succession of pre-formed elastomer articles, in particular tubes.
In this case, the term xe2x80x9celastomerxe2x80x9d should be understood in its broadest sense, of comprising articles which consist of any type of material with an elastomer base, with any type of reinforcement made of textile or of another type.
The term xe2x80x9cpre-formedxe2x80x9d is understood in this case in the sense of products which, before they are cured, are disposed on suitably shaped supports, such as to assume a shape which is then stabilized by the curing.
In general, curing of elastomer tubes which are continuous, and therefore not pre-formed, takes place by means of a discontinuous process, which consists of placing the tube to be cured, which has previously been bound and wound onto a bobbin, inside a curing autoclave, and generating inside the autoclave itself the conditions of temperature and pressure suitable for the curing process. On completion of the curing time, and a period of pause for normalization of the temperature and pressure, the autoclave is opened, and the bobbins are removed; the tube, which is now cured, will then be cut in order to meet the different requirements of use.
Although this process is of a discontinuous type, and therefore has pause times which have a negative impact on the total production time, it nevertheless makes it possible to obtain in a single operation a particularly large quantity of cured product, since a continuous tube can be wound onto a bobbin, and thus occupy a relatively small volume, even if it has a considerable length.
On the other hand, the above-described curing method is particularly disadvantageous in the case of pre-formed elastomer articles, such as pieces of tube which are fitted onto shaped supports, since in addition to the disadvantage of the pause times specific to the discontinuous process, there is that of the limited number of articles which can be loaded in the autoclave, so as to use fully the space available.
Curing ovens are also known which make possible a continuous curing process for continuous elastomer tubes. In particular, the tube to be cured passes continuously through these ovens, which for this purpose have respective input and output apertures for the tube itself, provided with corresponding sealing elements in order to maintain the curing conditions inside the oven, such as the pressure.
It is apparent that, whilst it is possible to produce an intake aperture and an output aperture which are provided with corresponding suitably shaped sealing elements, in order to permit sealed passage of a continuous tube with a substantially constant cross-section, this process becomes particularly complex, if not impossible, in the case of a plurality of pre-formed elastomer articles which advance in succession, and have variable shapes.
The object of the present invention is to provide an oven for continuous curing of a succession of pre-formed elastomer articles, which can eliminate simply and economically the disadvantages of the above-described known art.
On the basis of the invention, an oven is therefore provided for continuous curing of a succession of pre-formed elastomer articles, in particular tubes, characterized in that it comprises a curing chamber which communicates with the exterior via at least a first and a second aperture, means for admission of water vapour into the said curing chamber, in order to provide conditions of saturation of steam in the curing chamber itself, and means for movement, in order to advance the said pre-formed elastomer articles in succession along a path, which extends at least partially inside the said curing chamber, through the said first and second apertures.